The blastocyst is comprised of three layers. which of these layers will develope into the digestive and respiratory system?

Bulimia nervosa is characterized by a. a refusal to eat enough food to maintain normal, healthy body weight and/or the use of measures to produce severe weight loss. b. high fat intake and low level of physical activity. c. alternating binge eating and purging through vomiting, laxatives, or diuretics. d. normal food consumption interrupted by episodes of high consumption, resulting in obesity.

So i have a lot of answers answered but it says i still need to answer more questions. why is it doing that? how many questions need to be answered?

Fill in the blanks to complete the labels on this model of replicating dna! super